Airworthiness Directives; Saab Model SAAB SF340A and SAAB 340B Series Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Saab Model SAAB SF340A and SAAB 340B series airplanes, that requires repetitive inspections to detect cracking around certain fastener holes and adjacent areas of the front spar of the horizontal stabilizers; and corrective actions, if necessary. This amendment also requires repetitive x-ray inspections, cold working of certain fastener holes of the front spar of the horizontal stabilizers, and follow-on actions; and installation of new fasteners, which constitutes terminating action for the repetitive inspections required by this AD. This amendment is prompted by the issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent failure of the front spar due to fatigue cracking around certain fastener holes of the front spar of the horizontal stabilizers, which could result in reduced structural integrity of the airplane.